Engine operated generators are widely used as an electric source such as a temporary outdoor electric source and an emergency power supply. In case such engine operated generators are leisure or emergency equipment, a gas engine is often provided which uses fuel gas stored a small fuel receptacle, such as cassette fuel bottle.
The fuel gas is stored in the fuel receptacle in liquefied state and supplied to the gas engine in gasified state. When the operation of the gas engine is started and the fuel gas is supplied to the gas engine, the fuel gas stored in the fuel receptacle in liquefied state begins to be gasified under influence of reduction in the gas pressure to maintain the equilibrium between the liquid phase and the gas phase in the receptacle. For this reason, a large amount of latent heat of evaporation is needed, which reduces the temperature of the fuel receptacle. A fuel pressure regulator provided for regulating the pressure of the fuel gas is also caused to be reduced in temperature due to inflow of reduced-temperature fuel gas immediately after the gasification thereof and due to pressure reduction of the fuel gas itself.
If the temperature of the fuel receptacle is reduced excessively, gasification of the fuel gas becomes insufficient, so that the fuel gas pressure is reduced with a result that the fuel gas will not be supplied smoothly to the gas engine. As a measure to prevent this, it is known to heat the fuel receptacle by a heater in response to the temperature of the fuel gas receptacle and the gas pressure within the receptacle (For example, refer to Patent Documents 1 and 2).
On the other hand, a power control unit provided in the engine operated generator to control electric power generated by the electric generator, produces a large amount of heat due to its operation. A number of measures to cool the power control unit were known. Patent Document 3 discloses an engine operated generator having a sound proof case which encloses an engine, a generator and a control circuit unit (corresponding to the power control unit), wherein a box encasing the control circuit unit is provided with heat dissipating fins which are exposed to a cooling air inlet and are in contact with an end wall of the cooling air inlet.
Patent Document 1: JP 10-131810 A
Patent Document 2: JP 2671015 B
Patent Document 3: JP U 63-171632 A
The above-mentioned measure to heat the fuel receptacle by the heater has a problem in the manner of how the heater is provided and the manner to heat the receptacle, including how control of the heater is carried out without complication. Further, the cooling of the power control unit by cooling air involves a problem in that there are restrictions to the arrangement of the power control unit and its associated parts and complication in the structure.